Two or more vehicles may travel together to reduce fuel consumption. The vehicles may travel in series where one vehicle is the leader and follower vehicles align with the rear of the leader vehicle to form a nearly straight line of vehicles behind the leader vehicle. The lead vehicle may be exposed to undisturbed air, but follower vehicles are positioned in a slip stream of air behind the lead vehicle. The slip stream is a zone of moving air generated by the leader vehicle and following vehicles that reduce air being moved by following vehicles. Fuel consumption of both the leading and following vehicles may be improved when a group of vehicles travel in a formation utilizing a slip stream. However, there may also be disadvantages for a group of vehicles traveling in a close formation where they may benefit from the slip stream.
The inventors herein have recognized several disadvantages and have developed a method for operating vehicles, comprising: moving a vehicle from a lead position in a vehicle group to a first follower position within the vehicle group and moving a first following vehicle into the leading position in the vehicle group in response to a temperature of an emissions control device of the first following vehicle being less than a first threshold temperature.
By adjusting an order of vehicles in a vehicle platoon, it may be possible to maintain vehicle emissions even if operating vehicles within a slip stream of another vehicle tends to cool an emissions control device of a following vehicle. In one example, a following vehicle may request a leader position so that the following vehicle may operate at a higher engine load to increase the temperature of emissions control devices of a following vehicle so that emissions of the following vehicle may be maintained at lower levels. In addition, a leader vehicle may request to be repositioned in a vehicle platoon as a follower vehicle during conditions where an emissions control device of the leader vehicle is increasing higher than is desired.
The present description may provide several advantages. In particular, the approach may improve emissions of vehicles in a platoon over a travel distance. Further, the approach may improve opportunities to diagnose vehicles emissions control devices. Further still, the approach provides a way of arbitrating which vehicle occupies the leader position when one or more vehicles request the leader position so that emissions performance of the group of vehicles may be at a desirable level.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.